Weighing scale



March 4, 1952 c. e. HERBS? WEIGHING SCALE Fild April 16, 1948 INVENTOR. GL/FFORD 6. HERBST BY me ATTX Patented Mar. 4, 1952 WEIGHING SCALE Clifford G. Herbst, Waterbury, Conn., assignor to The Eastern Metalcraft Company, Incorporated, Waterbury, Conn., a corporation of Connecticut Application April 16, 1948, Serial No. 21,531

1 Claim. 1

This invention relates to Weighing scales, and more particularly to a scale of this type having a spring-supported platform and a pointer which will move over a graduated curved scale plate.

One object of this invention is to provide a device of the above nature which includes improved means for adjustably supporting the spring, and in which the platform is pivotally connected to said pointer and to a forked pivot plate parallel thereto.

Another object is to provide a device of the above nature having pivot lugs formed integral with the pointer and forked plate, whereby the cost of manufacture will be reduced and assem bly will be facilitated.

Another object is to provide a device of the above nature which includes an adjustable L- shaped bracket for supporting the scale mechanism, whereby the proper alignment of the mechanism may be easily obtained.

A further object is to provide a device of the above nature which will be simple in construction, inexpensive to manufacture, accurate, easy to assemble and adjust, compact, ornamental in appearance, very eificient and durable in use, q

and which will maintain its adjustment.

With these and other objects in view, there has been illustrated on the accompanying drawing one form in which the invention may conveniently be embodied in practice.

In the drawing,

Fig. 1 is a front elevation of the improved scale.

Fig. 2 is a rear elevation of the same,

Fig. 3 is a side elevation of the same.

Fig. 4 is a front elevation of the scale mechanism, with the base and the casing shown in section.

Fig. 5 is a side elevation of the same, with the base and the casing shown in section.

Fig. 6 is a bottom view of the scale.

Fig. 7 is a fragmentary plan view showing the spring-adjusting means.

Fig. 8 is a sectional view, taken substantially on the line 1-! of Fig. 6, showing the adjustable screw stud.

Fig. 9 is a fragmentary front view showing the connection of the spring with the yoke.

Fig. 10 is a view of the upper fork plate.

Fig. 11 is a view of the pivoted pointer-carrying plate and pointer arm formed thereon.

Referring now to the drawing in which like reference numerals denote correspoinding parts throughout the several views, the improved scale comprises a base H) which supports a casing H and a weighing pan I2.

The working mechanism of the scale is carried by an L-shaped bracket [3 comprising a horizontal top plate H which serves as the top Wall of the casing H, and a vertical back plate IS.

The back plate I5 is supported in engagement with the inner surfaces of a pair of abutting inturned rear flanges l6, I! of parallel casing side walls l8, l9, respectively. The top plate I4 of the bracket 13 is provided with a depending ear 20 at its rear edge which engages over the upper edges of the inturned flanges l6, l1, and has a plurality of side ears 2|, 2! which engage over the upper edges of the casing side walls I8, I9.

The side walls I 8, l9 are provided with ears 22 at their upper edges which pass through the top plate 14, and a plurality of ears 23 at their lower edges which are engaged through the base 10. The back plate [5 of the bracket I 3 also is provided with a single central ear 24 at its lower edge, engaged through the base I 0, said base being provided with a downturned inclined peripheral flange 25, which serves to support the ears 23, 24 out of contact with the surface upon which the scale rests, and also to reinforce the base l0. It will thus be seen that the base In, the L-shaped bracket 13, and the casing side walls IS, IS are firmly secured together as a rigid unit.

It will be noted that the base in is provided with a pair of apertures 26, 21 at each side of the ear 24, which provide access to lower edge portions of the back plate i5 of the bracket l3. The purpose of these apertures will be described hereinafter.

The front wall of the casing ll consists of a curved scale plate 28 which is secured against the curved front edges of the side plates I8, l9, by means of a bottom ear 29 which is engaged through the base ill, and an ear 3!) on the front edge of the to plate M which passes through the scale plate 28. Y

The scale pan i2 is carried above the casing it upon the upper ends of a pair of parallel vertical legs 3!, 32 of a U-shaped yoke 33 formed of flat metal material. A pair of slots 34 is provided in opposite edges of the top plate I4 in order to provide clearance for free vertical movement of the legs 3|, 32.

The U-shaped yoke 33 is supported within the casing II by means of a helical coiled weighing spring 35 which has its lower looped end engaged with a hook 38 struck up from the center portion of the yoke 33 and which is supported at its 3 upper end by means to be described hereinafter.

It will be understood that a weight placed upon the scale pan I2 will cause vertical movement of the yoke 33 to produce a proportional deflection of the weighing spring 35.

In order to maintain the yoke 33 upright at all times, provision is made of an upper short fork plate 31 and a lower elongated pointer-carrying plate 38, which plates are pivotally attached to the yoke 33 and to the back plate I of the bracket I3 in a parallelogram arrangement.

The attachment of the plates 31, 38 to the back plate I5 is by means of two pairs of integral fiat side pivot lugs 39 and 48, which are engaged in pairs of apertured ears 4 I, 42 respectively, bent inwardly from opposite edge portions of the back plate I5.

The attachment of the plates 31, 38 to the yoke 33 is by means of two pairs of integral flat side pivot lugs 43, 44, which are engaged in upper and lower pairs of apertures 45, 45, respectively, in the vertical legs 3|, 32, of the yoke 33.

It will be seen that the plates 31, 38 are of such a width as to hold the yoke 33 against substantial lateral deflection, whereby the yoke legs 3|, 32 Will be prevented from engaging the sides of the slots 34 and the side walls I8, |9,and interfering with the operation of the scales.

In order to provide full clearance for operation of the weighing spring 35, an open notch 41 and an oval-shaped aperture 48 are provided in the upper and lower fork plates 31, 38, respectively. The lower pointer-carrying plate 38 is extended forwardly in the form of a pointer arm 49 which passes outwardly through a vertical slot 50 in the curved scale plate 28, and carries a double-ended horizontal pointer 5| at its outer end Thus, the pointer 5| will move freely over the scale plate 28 to indicate the weight resting upon the scale pan I2.

The end of the pointer arm 49 will preferably be headed over at 52 in order to retain the pointer 5|, and is formed with a reduced neck 53 behind the pointer 5|, whereby the arm 49 is adapted to move freely in the slot 50. The slot 50 is provided with a central circular enlargement 54, which will facilitate the passage of the scale plate 28 over the pointer 5| during the assembly operation.

Referring now to Figs. 8 and 9. it will be seen that the weighing spring 35 is coiled in a righthand direction, whereby its upper end is adapted to be screwed upon the lower end of a threaded stud 55 which has opposite flat sides 55, and is supported in a fiat-sided aperture 51 in the top plate I4 by means of a nut 58.

Thus, it will be seen that by twisting the nut 58 the spring 35 may be adjusted and the stud 55 will be thereafter prevented from turning in the aperture 51.

In order to prevent the stud 55 from becoming lost in the interior of the scale, as would occur if the nut 58 were accidentally turned so far as to become disengaged from the stud 55, said stud is provided with an unthreaded upper end 59, which is incapable of passing through the nut 58.

The upper portion of the nut 58 is provided with an unthreaded counterbore 80 which will permit a greater range of adjustment by allowing the upper end 59 of the stud 55 to pass downwardly a certain distance into the nut 58.

' Accidental turning of the nut 58 will be prevented by means of a shallow hexagonal depression 5| which is adapted to serve as a seat for the hexagonal lower end of the nut 58 in the top plate I4. A conical coiled spring 82 is confined on the stud 55 between the lower surface of the top plate I4 and the upper end of the weighing spring 35, said spring 62 being concentric with the helical spring 35.

The lower side of the nut 58 will thus be retained resiliently in the depression BI 50 that the adjustment of the weighing spring 35 cannot change unless the nut 58 is forcibly turned. The threads of the stud 55 are prevented from interengaging with the edges of the aperture 51 by a pair of guide flanges 53 which are turned downwardly from the edges of said aperture, so that the weighing spring 35 may be smoothly and accurately adjusted.

Assembly In assembly, the scale pan I2 will first be secured to the upper end of the yoke legs 3|, 32, by any desired means, and the pointer 5| will be secured to the outer end of the pointer arm 49 by heading over the end of the arm 49 at 52.

The reduced neck 53 will provide an important advantage in. this operation, inasmuch as it provides abutments by means of which the arm 49 may be firmly supported to permit the heading operation.

The scale mechanism will then be assembled upon the L-shaped bracket I3 by inserting the pivot lugs 39, 48 of the plates 31, 38 in the pairs of cars 4|, 42, and by inserting the pivot lugs 43, 44 in the apertures 45, 48, of the yoke 33. The resiliency of the parts is such that they may be readily sprung into place without the use of any additional pivot members or securing elements which would require further manipulation.

The threaded stud 55 will then be entered downwardly through the nut 58 and the aperture 51 of the top bracket plate I4, whereupon the conical spring 52 will be applied over the lower endof the stud 55 and secured thereon by threading the upper end of the helical weighing spring 35 upon the lower end of said stud. The lower end of the weighing spring 35 will then be engaged with the central hook 36 on the base of the yoke 33.

The casing side plates I8, I9 will then be applied and secured by bending the ears 20, 2|, 22, whereupon the base IE! will be assembled by means of the cars 23, 24.

The scale plate 28 will then be assembled by passing the pointer 5| through the slot 50. This operation will be facilitated by the circular slot enlargement 58 which will permit the scale plate 28 to be turned degrees and allow the passage of the pointer 5| directly through the slot 58. The slot enlargement 54 may be omitted if desired, since the scale plate 28 may be so tipped as to permit entry of the pointer 5| through the slot. The cars 29, 38 will then be employed to secure the scale plate 28 in position.

After the scale parts have been assembled, if it is found that the pointer arm 49 engages with one side of the slot 58 due to slight inaccuracies in the manufacture or the handling of the parts, the mechanism may be readily adjusted to bring the pointer arm 49 into proper alignment with said slot 58, whereby the arm 49 will move freely therein without contacting either side thereof.

This adjustment may be accomplished by means of any suitable pointed instrument inserted through one of the apertures 25, 21 in the base I8 behind the vertical back plate I5 of the bracket I3, whereby either edge of the plate I5 may be pried forwardly. The back plate I 5 thus may be bent slightly, thereby swinging the pointer arm 49 to one side or the other depending upon which edge of the plate 15 is bent forwardly.

The weighing spring 35 will then be placed in proper adjustment by turning the nut 58, and the conical spring 62 will resiliently hold the nut 58 in the depression 8| so that it cannot turn accidentally. A scale plate 28, having suitable markings, will, of course, be used depending on the strength of the weighing spring 35.

One advantage of the improved weighing scale is that it may be made inexpensively entirely from sheet metal, excepting for the weighing spring and its supporting means.

Another advantage is that the fork plates 31, 38 may be stamped from fiat sheet metal integrally with their pivot lugs and require no auxiliary pivot members.

Another advantage is that the upper and lower support plates 31, 38 may be cut from sheet metal by the use of the same die, merely by applying strip metal of difference widths to the die.

Another advantage is that the reduced neck 53 of the pointer arm 39 avoids the necessity of twisting the pointer arm in order to provide clearance in the slot 50, and also provides an abutment for the operation of forming the headed end 52 when securing the pointer 5|.

Another advantage is that the means for supporting the weighing spring 35 is inexpensive to manufacture, reliable, and not likely to get out of order.

While there has been disclosed in this specification one form in which the invention may be embodied, it is to be understood that this form is shown for the purpose of illustration only, and that the invention is not to be limited to the specific disclosure, but may be modified and embodied in various other forms without departing from its spirit. In short, the invention includes all the modifications and embodiments coming within the scope of the following claim.

Having thus fully described the invention, what is claimed as new, and for which it is desired to secure Letters Patent, is:

In a weighing scale, a means for adjustably supporting a weighing spring including a top plate provided with an aperture therein having two oppoiste flat sides. a threaded stud in said aperture said stud having two opposite fiat sides slidably engaged with the flat sides of said aperture, a nut on said stud above said top plate, said nut having a non-circular periphery there being a shallow depression in said top plate surrounding said aperture adapted to serve as a seat for said nut and having a shape similar to the nut, said threaded stud being incompletely threaded at its upper end, whereby said nut cannot become accidentally disengaged therefrom.

CLIFFORD G. HERBST.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 200,386 Fredericks Feb. 19, 1878 504,534 Miller Sept. 5, 1893 612,968 Hansen 1 Oct. 25, 1898 632,525 Hansen Sept. 5, 1899 722,618 Pelouze Mar. 10, 1903 729,207 Mulligan May 26, 1903 749,497 Pelouze Jan. 12, 1904 749,498 Pelouze Jan. 12, 1904 752,874 Triner Feb. 23, 1904 821,035 Hansen May 22, 1906 1,289,885 Osborn Dec. 31, 1918 

